I just upgraded my Mid 2009 MacBook 160GB Drive to a 500GB drive. Initially I just cloned my original drive to the new drive, booted fined, doesn't recognize it as a 500GB drive. Launched disk utility to change partitions and it gave me the following error when trying to expand the current partition: mediakit reports partition map too small So then I tried to just add a new partition and got the following error: Chosen size is not valid for the chosen file system. I am just trying to either expand the MAC HD partition and add a second or if that cannot be done then just add a second partition where there is 340GB of free space. Any ideas? I am out of them. I am running the latest version of the OS.